Furnace conveyor roll



United States Patent() Filed Dec. 29, 1961, Ser. No. 163,298 7 Claims. (Cl. 263-6) The present invention relates to furnace conveyor rolls, and more particularly water cooled rolls that will have no appreciable cooling effect on the work they support.

In many furnaces that are used to heat slabs and the like, vthere are provided rolls to support the work and move it through the furnace. These rolls are ordinarily water cooled so that they will retain the strength necessary to support the work piece, but they shoutd be so constructed that -they will not have a cooling effect on the portion of the work engaging them, and thereby produce an nnevenly heated piece.

It is an object of the invention to provide a work supporting roll that will have suflicient strength to support a heavy work piece, and one that will have no appreciable cooling ef'fect on the work.

It is a further object of the invention to provide a furnace roll which Will forward work through a furnace without marring the surface of the work or causing cold spots.

In carrying out the invention, there is provided a refractory covered roll which has a work supporting, helical metal rib extending from its surface. This rib, along with the roll, is water cooled so that its strength is retained under heat. The ribis of such a size and shape that it will have a negligible effect on the work it supports.

The various features of novelty which characterize our invention are pointed out with panticularity in the claims annexed .to and forming a part of this specification. For a better understanding of the invention, however, vits advantages and specific objects attained with its use, reference should be had to the accompanying. drawings and descriptive matter in which we have illustra-ted and described a preferred embodiment of the invention.

In the drawings:

FIG. 1 is a view, partly in section, of the furnace rol-l,

FIG. 2 is a section taken on line 2 2 of FIG. l, and

FIG. 3 is a view, partly in section, of a modified form Y of rol-l. p

Referring to FIG. 1, there is shown lat 1 a portion of the side walls of a furnace with which the roll of the invention may be used. These side Walls are provided with axially aligned openings 2 through which the ends of the `roll extend. The roll itself comprises a plurality of par-ts, including a tubular supporting shaft 3, the left end of which is closed by an annular plug 4. An extension 5 is welded to the plug, and extends therefrom with the extension lbeing journaled for rotation in a bearing Y6. The right end of the roll is open, and is journaled for rotation in a bearing 7. The open end of this roll is received in a xture 8 that is provided with a drain pipe 9 extending from the lower end thereof. Openings 2 in the furnace -are arge enough so that the roll can be removed axially from the furnace when this becomes necessary. These openings are normally closed by means of annular plugs 11 of refractory material, which are supported by sheet metal plates 12 that are bolted to fthe furnace casing. The central openings of the plugs 11 can be a close .enough t with shaft 3 so that the furnace is to all intents and purposes sealed at the point where the ends of the roll project through the furnace walls.

A'tube 13 is located within the tubular shaft 3, with ice one end of this tube being fastened, preferably by Welding, vto a disc 14 that is also welded to the inner surface of vtube 3. The other end of tube `13 is closed by means of apdisc 15, leaving an annular space 16, open at one end, between tubes 3 and 13. This space can either be unobstructed except by suitable supports that are provided to hold tube 13 in concentric position, or it can be made into what amounts to a helical passage by means of a spacing member in the form of a rod 17 wound helically around tube 13.

A helical tube 18 is wound around and is fastened to the outer surface of the supporting shaft 43. This tube extends along shaft 3 for -a distance at least` equal to the load supporting portion of the shaft, and preferably to withinthe openings 2 in the furnace walls.v One end of the tube extends axially from yshaft 3, as at 19, to serve-as an inlet for cooling, water, while the other end of the tube extendsfthrough an opening provided in shaft 3` so that the Water supplied to tube 18 will be discharged into space 16 at the opposite end of the roll. This water will then ow either directly through space 16, if no rod 17 is used, or in a helical path through space 16 if the rod-17 is used, to be discharged from the right end of shaft 3 into xture S.

A load supporting rib or n 22 is fastened, preferably vby Welding, to extend radially from the outer surface of tube 18 to provide a. surface upon which work to be heated is supported as the roll is rotated. While lthis rib can be continuous from one end of the roll to the other, it is preferred to out it or to make it in sections with spaces 23 between these sections, as shown in the draw ing. These spaces al-low expansion of the rib without deformation as the roll is heated.

The entire roll, with the exception of the outer edge of rib 22, is covered with refractory material to protect it from the heat of the furnace. This material is shown as including an inner layer of insulating refractory material 24 which has a high insulating value and which covers the shaft 3` and tube .18. An outer layer of high temperature refractory materia-l `25 is placed over the material 24, and extends to within a short distance of the outer edge of rib 22. This refractory can be cast or molded. It is preferred to cast it in place, and for this reason it is desirable to use a reinforcing means to help hold the refractory in place between the convolutions of the rib. Such a reinforcing is shown as being in the form-of a relatively coarse mesh metal fabricor belt 26 that is placed between the convolutions of the rib and portion of the work will be engaged by the supporting roll, and that this portion will change from end to end of the Work and from roll to roll so that no cold spots will be developed on the surface of the work.

Water flowing through the tube 118 will keep this tube cool, and will draw enough heat from the rib to prevent the rib from reaching a temperature high enough for it to losse itsstrength. This water also circulates against the inner surface of load supporting member 3 to keep this member at a relatively low temperature. The insulating material around the shaft itself and the Water cooled tube 18 will successfully prevent heat from being drawn from the furnace and the work into the tube. Since the `surface of the refractory material 25 is substantially in the rfixture 8.

at furnace temperature the inner surface toward shaft 3 is at a relatively low temperature, the temperature drop across the refractory would be so severe that the refractory might well be harmed. For this reason, those portions of the refractory which are in engagement with the water cooled metal parts of the roll are made of an insulating material. Thus it will be seen that there is `provided a roll which will -support a heavy work piece being moved through -a furnace without drawing any appreciable amount of heat from the work, a roll that will not cause cold spots to vbe developed, and a roll which will be cooled sulliciently to retain its strength in a high 'temperature furnace.

The embodiment of the invention shown in FIG. 3 is intended vto be used in a lower temperature furnace `than that previously described. This form of the invention diifers from that of FIG. 1 only in the lmanner in which the cooling water is circulated through coil 1-8. In this'case, water supplied through a pipe 28 to the "left end of coil 18 where it flows through the coil in order to cool the rib 22. Water is discharged from coil 18 through an extension l29 which leads to `and discharges In vthis embodiment it will be seen that water is not circulated against the surface of tube 3 as was the case previously. Since it is intended that the roll be used in a lower temperature furnace, the refractory surrounding the roll will prevent the shaft 3t from becoming hot enough to lose its strength. It is` noted, however, that some heat is extracted from shaft 3 because `of engagement between this shaft and the tube 1S that made in the form of the apparatus disclosed vwithout departing from the spirit and scope ofthe invention set forth in the appended claims, and that in some cases certain features of our invention may be used to advantage without a corresponding use of other features.

What is claimed is:

l1. A furnace conveyor roll comprising in combination:

a tubular supporting shaft adapted to `extend across a furnace and having portions on each end to be received in bearings,

means forming an annular chamber within said shaft and extending axially thereof,

a tube Wrapped helically around said shaft with the helix adapted for extending at least the width of the work to be supported thereon, one end of said tube extending into said annular chamber and the other end of said tube serving as an inlet and extending through and beyond one end of said shaft,

a load supporting rib attached to and projecting radially from said tube,

a refractory material covering said shaft and tube with la portion of said rib extending beyond said material,

said annular chamber being open at the end of said shaft through which said other end of said tube extends, and

means at said last mentioned end of said shaft to collect a cooling fluid flowing from said end.

2. The combination of claim l including means in said annular chamber to form a helical path therein.

3. The combination of claim l in which said nib is formed of a plurality of individual sections aligned with each other.

4. A furnace conveyor roll comprising in combination:

ya tubular load supporting shaft having a portion on each end to be received in a bearing,

la tube wrapped around said shaft with the ends of the tube extending into the shaft,

a work engaging rib projecting radially outward from lsaid tube and extending lengthwise thereof, refractory material covering said shaft and tube and a portion of said rib whereby the work supporting portion of said rib extends beyond said refractory, and

means extending through one of said bearing portions of said shaft to one of the ends of said tube to supply a cooling lluid thereto.

5. A conveyor roll including in combination:

a tubular load carrying shaft,

a tube wound helically around said shaft,

a rib extending radially outward from said tube,

refractory material covering -said shaft, tube, and a portion of said rib whereby a portion of Said rib projects radially beyond said refractory material, and means to circulate a cooling lluid through said tube.

6. The combination of claim 5 including:

a tubular member concentrically located within said shaft to forman annular space between the two, and in which the means to circulate a cooling fluid includes means to supply the fluid to one end of said tube, means connecting the other end of the tube to said annular space, whereby the cooling iluid will ow through said tube into said annular space, and

means to direct cooling fluid flowing from said annular space to a drain.

7. The combination of claim 6 including means to direct cooling fluid flowing through said annular space ina helical path.

References Cited in the file of this patent UNITED STATES PATENTS 375,352. Handloser Dec. 27, 1887 FOREIGN PATENTS 768,209 France Aug. 2, 1934 

1. A FURNACE CONVEYOR ROLL COMPRISING IN COMBINATION: A TUBULAR SUPPORTING SHAFT ADAPTED TO EXTEND ACROSS A FURNACE AND HAVING PORTIONS ON EACH END TO BE RECEIVED IN BEARINGS, MEANS FORMING AN ANNULAR CHAMBER WITHIN SAID SHAFT AND EXTENDING AXIALLY THEREOF, A TUBE WRAPPED HELICALLY AROUND SAID SHAFT WITH THE HELIX ADAPTED FOR EXTENDING AT LEAST THE WIDTH OF THE WORK TO BE SUPPORTED THEREON, ONE END OF SAID TUBE EXTENDING INTO SAID ANNULAR CHAMBER AND THE OTHER END OF SAID TUBE SERVING AS AN INLET AND EXTENDING THROUGH AND BEYOND ONE END OF SAID SHAFT, A LOAD SUPPORTING RIB ATTACHED TO AND PROJECTING RADIALLY FROM SAID TUBE, A REFRACTORY MATERIAL COVERING SAID SHAFT AND TUBE WITH A PORTION OF SAID RIB EXTENDING BEYOND SAID MATERIAL, SAID ANNULAR CHAMBER BEING OPEN AT THE END OF SAID SHAFT THROUGH WHICH SAID OTHER END OF SAID TUBE EXTENDS, AND MEANS AT SAID LAST MENTIONED END OF SAID SHAFT TO COLLECT A COOLING FLUID FLOWING FROM SAID END. 